1. Field of the Invention
The present invention generally relates to the field of test equipment for the automotive industry. More particularly, the present invention relates to the field of test devices for indicating short circuits or draws in automotive wiring of vehicles.
2. Description of the Prior Art
Specifically, test equipment are well known in the art. A wide variety of sophisticated test equipment has been made available for troubleshooting and adjusting the various systems of vehicles. Most of the test equipment used for vehicle testing and maintenance employs electronic circuitry, which can range from the relatively simple to substantially complex. As a result, more complex electronic text equipment tends to be expensive, fragile and relatively large. However, it is desirable to perform simple electrical diagnostic tests on vehicle wiring systems, such as the presence of voltages.
The following twenty-two (22)prior art patents are found to be pertinent to the field of the present invention:
1. U.S. Pat. No. 2,382,647 issued to McLoughlin et al. on Aug. 14, 1945 for xe2x80x9cElectrical Wiring Systemxe2x80x9d (hereafter the xe2x80x9cMcLoughlin Patentxe2x80x9d);
2. U.S. Pat. No. 2,625,596 issued to Hines on Jan. 13, 1953 for xe2x80x9cCircuit Checking Apparatusxe2x80x9d (hereafter the xe2x80x9cHines Patentxe2x80x9d);
3. U.S. Pat. No. 2,643,370 issued to Lawrence on Jun. 23, 1953 for xe2x80x9cElectric Circuit Checking Equipmentxe2x80x9d (hereafter the xe2x80x9cLawrence Patentxe2x80x9d);
4. U.S. Pat. No. 3,074,013 issued to Bowden on Jan. 15, 1963 for xe2x80x9cDevice For Indicating Short Circuitsxe2x80x9d (hereafter the xe2x80x9cBowden Patentxe2x80x9d);
5. U.S. Pat. No. 3,699,433 issued to Smith, Jr. on Oct. 17, 1972 for xe2x80x9cShort Circuit Locator Apparatus Including A Plurality Of Intermittently Operated Circuit Breakersxe2x80x9d (hereafter the xe2x80x9cSmith Patentxe2x80x9d);
6. U.S. Pat. No. 3,786,466 issued to Naito et al. on Jan. 15, 1974 for xe2x80x9cElectrical Leakage Detecting Devicexe2x80x9d (hereafter the xe2x80x9cNaito Patentxe2x80x9d);
7. U.S. Pat. No. 3,829,763 issued to Morin on Aug. 13, 1974 for xe2x80x9cAutomotive Voltage And Continuity Testerxe2x80x9d (hereafter the xe2x80x9cMorin Patentxe2x80x9d);
8. U.S. Pat. No. 3,973,193 issued to Hayes on Aug. 3, 1976 for xe2x80x9cElectric Light Tester And Unit Operating Devicexe2x80x9d (hereafter the xe2x80x9cHayes Patentxe2x80x9d);
9. U.S. Pat. No. 4,028,621 issued to Bloxam on Jun. 7, 1977 for xe2x80x9cPortable Automotive Test Probexe2x80x9d (hereafter xe2x80x9cthe ""621 Bloxam Patentxe2x80x9d);
10. U.S. Pat. No. 4,095,172 issued to Strand on Jun. 13, 1978 for xe2x80x9cVehicle Antenna Testerxe2x80x9d (hereafter the xe2x80x9cStrand Patentxe2x80x9d);
11. U.S. Pat. No. 4,177,420 issued to Tripp on Dec. 4, 1979 for xe2x80x9cMajor And Minor Short Leakage Detectorxe2x80x9d (hereafter the xe2x80x9cTripp Patentxe2x80x9d);
12. U.S. Pat. No. 4,207,517 issued to Bloxain on Jun. 10, 1980 for xe2x80x9cSwitchless D.C. Multifunction Testerxe2x80x9d (hereafter xe2x80x9cthe ""517 Bloxam Patentxe2x80x9d);
13. U.S. Pat. No. 4,366,434 issued to Ellis on Dec. 28, 1982 for xe2x80x9cVoltage Detectors And Electrical Continuity Checkersxe2x80x9d (hereafter the xe2x80x9cEllis Patentxe2x80x9d);
14. U.S. Pat. No. 4,584,526 issued to Lobastov on Apr. 22, 1986 for xe2x80x9cCombination Continuity And Live Circuit Path Testerxe2x80x9d (hereafter the xe2x80x9cLobastov Patentxe2x80x9d);
15. U.S. Pat. No. 4,689,573 issued to Hilmer on Aug. 25, 1987 for xe2x80x9cOn-Vehicle Diagnostic Unit For Electronic Ignition Systemsxe2x80x9d (hereafter the xe2x80x9cHilmer Patentxe2x80x9d);
16. U.S. Pat. No. 4,740,745 issued to Sainz on Apr. 26, 1988 for xe2x80x9cPolarity And Continuity Tester For Primary And Secondary Automotive Circuitsxe2x80x9d (hereafter the xe2x80x9cSainz Patentxe2x80x9d);
17. U.S. Pat. No. 4,878,025 issued to Persson on Oct. 31, 1989 for xe2x80x9cTrouble Finder For Testing An Electrical System Of A Vehicle For Short-Circuitingxe2x80x9d (hereafter the xe2x80x9cPersson Patentxe2x80x9d);
18. U.S. Pat. No. 4,999,574 issued to Stephens on Mar. 12, 1991 for xe2x80x9cSwitchable Automotive Circuit Test Lightxe2x80x9d (hereafter the xe2x80x9cStephens Patentxe2x80x9d);
19. U.S. Pat. No. 5,030,916 issued to Bokitch on Jul. 9, 1991 for xe2x80x9cAuto Electric Testerxe2x80x9d (hereafter the xe2x80x9cBokitch Patentxe2x80x9d);
20. U.S. Pat. No. 5,367,250 issued to Whisenand on Nov. 22, 1994 for xe2x80x9cElectrical Tester With Electrical Energizable Test Probexe2x80x9d (hereafter the xe2x80x9cWhisenand Patentxe2x80x9d);
21. U.S. Pat. No. 5,604,439 issued to Walkington et al. on Feb. 18, 1997 for xe2x80x9cTractor/trailer Lamp Circuit Continuity Test Devicexe2x80x9d (hereafter the xe2x80x9cWalkington Patentxe2x80x9d); and
22. French Patent No. 2662-257 for xe2x80x9cPositive And Negative Voltage Checker For Vehicle Wiringxe2x80x9d (hereafter the xe2x80x9cFrench Patentxe2x80x9d).
The McLoughlin Patent discloses an electrical wiring system. It comprises a pair of lamps which are used to determine whether or not a fault exists. The load is connected across the mains having isolator switches in the positive and negative sides. The device of the McLoughlin Patent utilizes a 24-volt system.
The Hines Patent discloses a circuit checking apparatus.
The Lawrence Patent discloses an electric circuit checking equipment.
The Bowen Patent discloses a device for indicating short circuits. It comprises a plurality of lamp bulbs connected in parallel. A three-pole double throw switch is operable to one position when the device is used for locating a short circuit in a vehicle having a 6-volt system and to another position to condition the device for operation on a 12-volt system.
The Smith Patent discloses a short circuit locator apparatus including a plurality of intermittently operated circuit breakers.
The Naito Patent discloses an electrical leakage detecting device.
The Morin Patent discloses an automotive voltage and continuity tester. The tester includes an indicator branch having in series a pair of indicating lamps. One side of a battery is connected to a first terminal point of the indicating branch and a first test lead is connected to the other side of the battery. A second test lead is connected to the second terminal point of the indicating branch, so that when the pair of test leads are connected to a common conductor for testing continuity, the battery potential is applied at the terminal points of the indicator branch. A switched shorting branch is connected between the first terminal point and the junction of the indicator lamps.
The Hayes Patent discloses an electrical light tester and unit operating device. The ""621 Bloxam Patent discloses a portable automotive test for rapidly and flexibly troubleshooting automotive electrical systems. The test probe features highly reliable electronic circuits energized from an automotive battery through a pair of connectors for connection to the terminals of the battery. A conductive test probe and a pair of indicator lamps are housed within a hand-held probe housing and enable an operator to rapidly trouble shoot the entire electrical system without alteration of any kind to the battery terminal connections.
The Strand Patent discloses a vehicle antenna tester.
The Tripp Patent discloses a major and minor short leakage detector. It comprises a current lead for connection to the positive battery terminal from which the battery cable has been disconnected, a sensor lead for connection to the disconnected cable, a silicon controlled rectifier and vehicle light bulbs connected across the leads for dissipating high currents caused by a major short, a trigger transistor connected across the leads for turning the rectifier on in response to the current drawn by any short, a minor short oscillator and a speaker for producing a constant frequency tone that signals a minor short, a major short oscillator for modulating the minor short oscillator causing it to produce a warbling tone that signals a major short, and a discriminator transistor responsive to the amount of current flowing across the leads for energizing the major short oscillator only in the presence of a major short.
The ""517 Bloxam Patent discloses a self-contained handheld portable pocket probe.
The Ellis Patent discloses voltage detectors and electrical continuity checkers.
The Lobastov Patent discloses a combination continuity and live circuit path tester.
The Hilmer Patent discloses an on-vehicle diagnostic unit for electronic ignition systems.
The Sainz Patent discloses a polarity and continuity tester for primary and secondary automotive circuits.
The Persson Patent discloses a trouble finder for testing an electrical system of a vehicle for short-circuiting. It comprises an oscillator which limits the current at the output to near 0 A as long as short-circuiting remains. When the short-circuiting ceases, this is detected by a unit of sensitivity and as a result of this, the oscillation stops and reset current and voltage levels are entered immediately and automatically.
The Stephens Patent discloses a switchable automotive circuit test light tool. The tool comprises a case to hold a probe, circuit, LED""s and means to connect the tool to an automobile. A first light tells the operator the tool is ready for use and that the electrical connections to the storage battery are complete to a second light. The second light illuminates when the probe is in contact with the automobile system and continuity of the circuit exists. A switch on the tool selects current direction.
The Bokitch Patent discloses an auto electric tester which includes a casing, circuitry mounted within the casing and four electrical conductors extending from the casing and connected to the circuitry.
The Whisenand Patent discloses an electrical tester with an electrical energizable test probe.
The Walkington Patent discloses a tractor/trailer lamp circuit continuity test device. It comprises an auxiliary plug-and-socket assembly which has a plurality of pins at one end which plug into a socket at the rear end of a tractor vehicle and sockets at the other end which receive a plug form a trailer vehicle.
The French Patent discloses a positive and negative voltage checker for vehicle wiring.
None of these prior art patents have disclosed a test device for indicating a short circuit in automotive wiring of a vehicle utilizing a 12-volt electrical system. It is desirable to provide a test device that is simple in construction, easier to manufacture and can expedite the location of short-circuits or draws in automotive wiring more easily than known prior art.
The present invention is a unique test device for indicating short-circuits in automotive wiring of a vehicle utilizing a 12-volt electrical system.
The test device comprises two incandescent lamps connected on opposite sides of a resettable circuit breaker. Each incandescent lamp has a positive terminal and a negative terminal. The circuit breaker has a first terminal which is connected to the negative terminal of the first lamp and a second terminal which is connected to the positive terminal of the second lamp for protecting the automotive wiring and the test device from electrical damage.
A first test lead has one end which is connected to the positive terminal of the first lamp and the other end is connected to a first connector and being connectable to a first side of a fuse junction. A second test lead has one end which is connected to the positive terminal of the second lamp and the other end is connected to a second connector and being connectable to a second side of the fuse junction. A ground lead has one end which is connected to the negative terminal of the second lamp while the other end is connected to a third connector and being connectable to a ground or chassis of the vehicle. The test device is connected with the fuse junction of a particular electrical circuit of the vehicle while the fuse is removed, wherein when the second lamp is illuminated, then everything is normal and the particular electrical circuit of the vehicle is healthy, but if the second lamp is not illuminated and the first lamp is illuminated, this means that there is a short-circuit or draw being made on the particular electrical circuit of the vehicle causing the power to go out and illuminate the first lamp.
It is an object of the present invention to provide a test device that is simple and effective for indicating a short circuit or a draw in automotive wiring of a vehicle when a short circuit develops in the automotive wiring.
It is a further object of the present invention to provide a test device which facilitates the location of a short-circuit or a draw in automotive wiring.